"Historically, cannabis has been linked to really early use with yoga in ancient Shiva cults," said Dee Dussault, 34, a 20-year yogi and instructor of Ganja Yoga in San Francisco, which launched this October. "Back then, they weren't smoking it, but drinking it in a milk beverage and burning it as an incense. But if you're burning incense, you're essentially hotboxing the temple as a result."

At Ganja Yoga, students are responsible for their own high: Those who possess medical marijuana cards can participate in a 15-minute smoking session before class, at which point everyone will form a circle, state their name and share their inspiration for attending.

"A lot of students are consuming it before yoga anyway," said Dussault. "So a big benefit that I am hearing is the community aspect. The first thing they want to do after consuming cannabis is lay down and stretch. And, depending upon the dosage and strain, it really encourages people to relax."

Described as primarily a meditative or a mental practice, Dussault focuses on slow-moving Hatha yoga poses that promote joint mobility and are approachable for different body types. The classes -- which are held on Wednesdays at Merchants of Reality studio in the Bay Area -- average around 16 students at a time and are typically divided equally between female and male practitioners, she said.

"Far more men attend Ganja Yoga classes than any of the others I teach," said Dussault, who also leads sessions of Clothing-Free Yoga, Tantra and Sexual Awakening Yoga, among others.

The class has proved so popular, in fact, that there is talk of adding additional times to the studio schedule.

This may come as little surprise to Atwater Yoga in Los Angeles, which has offered a 4:20 Yoga class on weekends since 2010, with the name coming from a code phrase for cannabis consumption.

"I don’t encourage dependence on cannabis or claim that it should always be paired with yoga, but it certainly is a way to explore inner space, which is my main mission as a yoga teacher," wrote Liz McDonald, who founded the class, on the 4:20 Yoga site.

As with Ganja Yoga, students of 4:20 Yoga must arrive medicated and are not allowed to consume or smoke cannabis in class.

Over the last year, pot-friendly yoga classes have also begun to spring up in Colorado, where legislation made recreational use legal in 2014. There it is more likely for students to bring edibles or other cannabis items into the studio for consumption.

But not everyone is a believer in blending the two activities.

"What yogis should remember, is that real enlightenment and reaching Samadhi won’t come from a weed, it comes from hard work and persistent practice," said Julie Philips-Turner, founder of Chesapeake Yoga & Wellness, in a recent blog on the subject. "A good practice includes complete faith, continued uninterrupted, for a long time -- this is the way to achieve the state of yoga."